电路功能与优势
图1所示电路使用AD5700(业界功耗最低、尺寸最小的
HART
1
兼容型IC调制解调器)以及AD5420(一款16位电流输
出DAC)，形成完整的HART兼容型4 mA至20 mA解决方案，
这在环路供电变送器的应用中非常常见。
为了进一步节省空间，AD5700-1提供了精度为0.5%的内部
振荡器。
连接/参考器件
电路笔记
CN-0270
Circuits from the Lab® reference designs are engineered and
tested for quick and easy system integration to help solve today’s
analog, mixed-signal, and RF design challenges. For more
information and/or support, visit www.analog.com/CN0270.
AD5700,
AD5700-1
低功耗HART®调制解调器
AD5420 16位4 mA至20 mA DAC
完整的4 mA至20 mA HART解决方案
I
OUT
LATCH
AD5420
AD5700
SCLK
SDIN
SDO
GND
CLEAR
FAULT
REFOUT
REFIN
4mA TO 20mA
CURRENT LOOP
0.1µF
0.1µF
10µF
DIGITAL
INTERFACE
UART
INTERFACE
10.8V TO 36V2.7V TO 5.5V
HART_OUT
DGND
TXD
RXD
RTS
CD
V
CC
ADC_IP
REF
150pF
0.1µF
1µF
18Ω
10kΩ
1.2MΩ
1.2MΩ
300pF
150kΩ
C1
4.7nF
*C2
*NC
R
SET
DV
CC
AV
DD
CAP2 CAP1
R
L
15kΩ
R
H
27kΩ
C
H
8.2nF
C
L
4.7nF
AGND
0.1µF
10µF
10564-001
图1. AD5420 HART电路简化原理图
1
HART®是HART通信基金会的注册商标。
Rev. B
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Devices engineers. Standard engineering practices have been employed in the design and
construction of each circuit, and their function and performance have been tested and veried in a lab
environment at room temperature. However, you are solely responsible for testing the circuit and
determining its suita
bility and applicability for your use and application. Accordingly, in no event shall
Analog Devices be liable for direct, indirect, special, incidental, consequential or punitive damages due
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All rights reserved.
评估和设计支持
电路评估板
CN-0270评估板(EVAL-CN0270-EB1Z)包括USB-SWD/
UART-EMUZ
设计和集成文件
原理图、布局文件、物料清单
评论0